56 Mr. S. H. ScudJer on Mesozoic Cockroaches. 



ally increasing in obliquity distally until they form an angle 

 of 45° with it ; they are slightly curved, the concavity out- 

 ward, very closely crowded, and about every third one forked 

 near the middle, but with no regularity. The scapular 

 branches are not preserved, but as in P. pluma, and for the 

 same reason, they probably resemble P. chrysea rather than 

 P. intermixta. The externomedian branches are very closely 

 crowded, generally straight, part from the stem at an angle 

 of 45° next the base, and become almost wholly longitudinal 

 at the apex ; they fork about as frequently as, and more irre- 

 gularly than, the mediastinal branches. The internomedian 

 area extends far out on the wing, and its branches (what few 

 can be seen) resemble those of the preceding area, and at its 

 extremity are parallel to them. Length of fragment 13 

 millim., width 9 millim. ; probable length of wing 15 millim., 

 probable width 9 millim. 



Described from a specimen from the English Purbecks 

 sent me for examination by Eev. P. B. Brodie, 



It is not impossible that the fragment of a larger wing 

 figured by Westwood (Quart. Joui-n. Geol. Soc. Lond. 1854, 

 pi. xvii. fig. 7), from the Lower Purbecks of Durdlestone Bay, 

 may be a species very close to this. 



Pterinohlattina chrysea. 



Blattina chrysea, E. Geinitz, Zeitsctr. deutsch. geol. Gesellscb. 1880, 

 p. 520, pi. xxxii. fig. 2, 



In this case we have a more perfect wing, the tip being 

 almost completely preserved. The mediastinal vein termi- 

 nates before the middle of the outer half of the costal border, 

 and is furnished with simple, straight, oblique branches, not 

 so numerous as in the other species, to judge by the figure, 

 though they are spoken of by Geinitz as " very numerous 

 and closely crowded," Just before the scapular reaches the 

 tip of the mediastinal, it turns parallel to the costal margin, 

 runs to the upper tip of the wing, and emits branches similar 

 to those of the mediastinal, but of course of equal length. All 

 the externomedian branches run almost longitudinally, are 

 straight, sometimes forked, and appear from the figure to be 

 less crowded than the mediastinal branches, though they are 

 compared by Geinitz to the barbs of a feather. The interno- 

 median runs to just beyond the broadest part of the wing, 

 being thus longer than the mediastinal, and sends less crowded, 

 gently curved, usually forked, rather short branches to the 

 border. The few anal branches curve and strike the inner 

 margin. Length 5 millim., breadth about 2-25 millim. 



